PROBLEM TO BE SOLVED: To provide a blood coagulation tube accommodating a blood separating medium that can improve the solubility of an anticoagulant appreciably and allow an application of an anticoagulant of an accurate amount. SOLUTION: The blood collection tube comprises a bottomed tube body 1, a rubber plug 2 for stopping up the mouth of the tube body 1, a blood separating medium 4 contained in the tube body 1, and a cylindrical sleeve 3 set near the blood separating medium 4. The sleeve 3 has a leading end 31, which is nearer to the blood separating medium 4, and a base end 32. The leading-end- side inside diameter of the sleeve 3 gradually expands toward the leading end 31 to have a thinner wall, and a crimped internal wall of the sleeve 3 has thereon an application of an anticoagulant. In centrifugation with blood filling the tube body 1, the blood separating medium 4 is allowed to move smoothly along the internal wall of the sleeve 3.
